CN110208594A - A kind of protector circuit protection detection system - Google Patents
A kind of protector circuit protection detection system Download PDFInfo
- Publication number
- CN110208594A CN110208594A CN201910609622.7A CN201910609622A CN110208594A CN 110208594 A CN110208594 A CN 110208594A CN 201910609622 A CN201910609622 A CN 201910609622A CN 110208594 A CN110208594 A CN 110208594A
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- phase
- protector
- detection
- detection unit
- high resistant
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- 238000001514 detection method Methods 0.000 title claims abstract description 80
- 230000001012 protector Effects 0.000 title claims abstract description 36
- 230000005611 electricity Effects 0.000 claims abstract description 24
- 238000002955 isolation Methods 0.000 claims abstract description 19
- 238000004804 winding Methods 0.000 claims description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 4
- 230000007257 malfunction Effects 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims 1
- 238000012544 monitoring process Methods 0.000 abstract description 3
- 239000000523 sample Substances 0.000 description 10
- 239000004020 conductor Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 6
- 230000007935 neutral effect Effects 0.000 description 6
- 238000005259 measurement Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- 210000000080 chela (arthropods) Anatomy 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 206010033799 Paralysis Diseases 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 208000003663 ventricular fibrillation Diseases 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16566—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533
- G01R19/16576—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 comparing DC or AC voltage with one threshold
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/08—Measuring resistance by measuring both voltage and current
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/20—Measuring earth resistance; Measuring contact resistance, e.g. of earth connections, e.g. plates
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/16—Measuring asymmetry of polyphase networks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention discloses a kind of protector circuits to protect detection system; it includes programmable logic device; programmable logic device is connected with A/D sample circuit and operation relay; A/D sample circuit is connected with high resistant isolation circuit, and high resistant isolation circuit is connected separately with three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit；Three-phase electricity detection unit, earthing detection unit connect to be electrically connected with the Three-phase five-wire of protector power supply with detection of electrical leakage unit.This programme is used on protector, real-time monitoring is carried out to electricity safety in protector by three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit, guarantee the normal operation of equipment, understand Electrical Safety information in real time, fills up the market vacancy that existing current protector has a single function.
Description
Technical field
The present invention relates to protector technical fields, and in particular to a kind of protector circuit protection detection system.
Background technique
To field work car equipment power supply when can monitor in real time, power supply occur overvoltage protection, under-voltage protection,
When the failures such as open-phase protection, fault-phase protection by way of relay exports, provides the user with warning output and protection circuit is dynamic
Make the touching point control signal exported, play alarm and protective effect, to guarantee that electrical equipment operates normally.
Due to the frequent replacement operation place of field work vehicle, whether ground line can also follow vehicle to change position, connect
In fact, connecing jail all can bring immeasurable loss to power supply unit, instrument and personnel safety in vehicle.
The vehicle of field work at present is equipped with vehicle-mounted distribution protector, it was used to ensure personal safety
Press protection philosophy, safe voltage be set in certain value, be such as set in 36V, but when drench with rain open work when, it is simultaneously dangerous, electricity
Though pressure is not high, too strong electric current can cause the ventricular fibrillation of people to lead to death.Under normal circumstances, the electric current of 1mA passes through human body
When feel, 25mA or more human body is difficult to get rid of, 50mA i.e. be in peril of one's life, electric current mainly cause heart stop and exhale
Inhale paralysis.Bigger by the electric current of human body, the damage to human body is also more serious.So over-voltage earth detector and different
Dingan County is complete.
Summary of the invention
For the above-mentioned deficiency of the prior art, the present invention provides a kind of security personnel of achievable multifunctional circuit safety detection
Device circuit protection detection system.
To achieve the above object of the invention, the technical scheme adopted by the invention is as follows:
There is provided a kind of protector circuit protection detection system comprising programmable logic device, programmable logic device are connected with
A/D sample circuit and operation relay, A/D sample circuit are connected with high resistant isolation circuit, and high resistant isolation circuit is connected separately with
Three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit；Three-phase electricity detection unit, earthing detection unit connect and leak electricity
Detection unit is electrically connected with the Three-phase five-wire of protector power supply.
Further, three-phase electricity detection unit includes over-voltage indicator light, under-voltage indicator light and phase shortage indicator light, over-voltage instruction
Lamp, under-voltage indicator light and phase shortage indicator light are connect with programmable logic device.
Further, earthing detection unit includes auto-transformer T1, the termination of tap-changing windings one three of auto-transformer T1
Five line firewire of phase, the zero curve and high resistant isolation circuit of another termination Three-phase five-wire；The voltage adjusting end of auto-transformer T1 passes through conducting wire
Connect ground terminal and high resistant isolation circuit, be provided with current transformer Ta between voltage adjusting end and ground terminal, current transformer Ta with
Circuit connection is isolated in high resistant.
Further, earthing detection unit includes ground fault indicator light, and malfunction indicator lamp is connect with programmable logic device.
Further, detection of electrical leakage unit includes current transformer Tb, the phase line in the Three-phase five-wire of protector power supply and
Zero curve passes through the annular core of current transformer Tb, and circuit connection is isolated with high resistant in the output lead of current transformer Tb.
Further, concatenated test button SB and current-limiting resistance RL is connected between the zero curve and firewire of Three-phase five-wire.
Further, detection of electrical leakage unit further includes PE line, and the both ends of PE line are separately connected the zero curve of Three-phase five-wire, equipment
Shell and high resistant isolation circuit.
Further, LED display panel and parameter setting panel are also connected on programmable logic device.
The invention has the benefit that this programme is used on protector, pass through three-phase electricity detection unit, earthing detection list
Member and detection of electrical leakage unit carry out real-time monitoring to electricity safety in protector, guarantee the normal operation of equipment, understand use in real time
Electric security information has filled up the market vacancy that existing current protector has a single function.Three-phase electricity detection unit passes through protector is electric
The Three-phase five-wire in source is directly accessed in A/D sample circuit, is sampled to voltage, and the mark in programmable logic device with setting is inputted
Quasi- value is compared, if the voltage of sampling is higher or lower than standard value, proves over-voltage or under-voltage problem occurred；It is programmable to patrol
It collects device and closes operation relay immediately, and alarm.
Earthing detection unit uses double pincers method measurement of Grounding Resistance values, easy to operate, can be in continuous switch power supply, normal
Tested when work, it is not necessary to be inserted into measuring probe, tested electrode need not also be separated, it is only necessary to double clamps earth conductor just
Ground resistance can be measured: precision is high, and precision can achieve 0.01 Ω；Strong antijamming capability can filter out various power frequencies
Harmonic wave.
Earthing detection unit is furnished with auto-transformer T1 (voltage clamp) and current transformer Ta (current clamp), auto-transformer
T1 provides a potential E in the loop, and generates electric current I in tested circuit, by the measurement to E and I, by Ohm's law: R
=E/I can acquire the value of ground resistance；And the ground resistance standard value for being input to programmable logic device and setting is compared
Compared with judging whether to meet the requirements.If after being judged as failure, output control signal disconnects operation relay, to reach cutting master
Circuit, the purpose for protecting electrical equipment and life safety.
The PE line termination device shell of detection of electrical leakage unit, other end independent grounding or access zero curve；Work as equipment leakage,
When its shell voltage-to-ground reaches programmable logic device setting danger numerical value, operation relay is disconnected, is cut off the power.It is protected
Three-phase five-wire and the neutral conductor pass through the ring-shaped core of current transformer Tb, constitute the primary coil of mutual inductor, are wrapped in annular
Winding on iron core constitutes the secondary coil of current transformer Tb, if not leaking electricity generation, at this moment flow through three-phase phase line and
The current vector of the neutral conductor and it is equal to zero, therefore corresponding induced electromotive force can not be generated on secondary coil.If it happens
Electric leakage, three-phase phase line, the neutral conductor current vector and be not equal to zero, just make to generate induced electromotive force on secondary coil, this
Signal will be sent in programmable logic device, disconnect operation relay.
Since detection of electrical leakage unit is a protective device, it is whether intact, reliable that it should be inspected periodically.Pass through test
Can the series connection of button SB and current-limiting resistance RL be simulated leakage path, be operating normally with check device.LED display panel is used for
The data information for showing detection, can set various standard values in programmable logic device by parameter setting panel.
Detailed description of the invention
Fig. 1 is the electrical schematic diagram of protector and circuit protection detection system.
Fig. 2 is the schematic diagram of earthing detection unit.
Fig. 3 is the schematic diagram of detection of electrical leakage unit.
Fig. 4 is the schematic diagram of three-phase electricity detection unit.
Fig. 5 is the circuit diagram of A/D sample circuit.
Fig. 6 is the circuit diagram of high resistant isolation circuit.
Specific embodiment
A specific embodiment of the invention is described below, in order to facilitate understanding by those skilled in the art this hair
It is bright, it should be apparent that the present invention is not limited to the ranges of specific embodiment, for those skilled in the art,
As long as various change is in the spirit and scope of the present invention that the attached claims limit and determine, these variations are aobvious and easy
See, all are using the innovation and creation of present inventive concept in the column of protection.
As shown in Figure 1, the circuit protection detection system of protector includes programmable logic device, programmable logic device is connected with
The operation relay of A/D sample circuit and protector, A/D sample circuit are connected with high resistant isolation circuit, high resistant isolation circuit point
It is not connected with three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit；Three-phase electricity detection unit, earthing detection unit
It is electrically connected with the Three-phase five-wire of protector power supply with detection of electrical leakage unit.Programmable logic device is programmable using EPM series of PLC
Logic controller.
This programme is used on protector, passes through three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit pair
The safety of protector carries out real-time monitoring, guarantees the normal operation of equipment, understands Electrical Safety information in real time, has filled up existing mesh
The market vacancy that preceding protector has a single function.As shown in Figure 5 and Figure 6, A/D sample circuit and high resistant isolation circuit are realized pair jointly
Each unit voltage is sampled in acquisition system, and is inputted programmable logic device and handled.
As shown in figure 4, three-phase electricity detection unit includes that over-voltage indicator light, under-voltage indicator light and phase shortage indicator light, over-voltage refer to
Show that lamp, under-voltage indicator light and phase shortage indicator light are connect with programmable logic device.Three-phase electricity detection unit passes through protector is electric
Phase line and zero curve are directly accessed in A/D sample circuit in the Three-phase five-wire in source, are sampled to voltage, and programmable logic device is inputted
In be compared with the standard value of setting, if sampling voltage be higher or lower than standard value, prove over-voltage or under-voltage occurred
Problem；Programmable logic device closes operation relay immediately, and alarms.
As shown in Fig. 2, earthing detection unit includes auto-transformer T1, the termination of tap-changing windings one three of auto-transformer T1
A piece firewire of five line of phase, the zero curve and high resistant isolation circuit of another termination Three-phase five-wire；The voltage adjusting end of auto-transformer T1 is logical
Conducting wire connection ground terminal and high resistant isolation circuit are crossed, current transformer Ta, Current Mutual Inductance are provided between voltage adjusting end and ground terminal
Circuit connection is isolated with high resistant in device Ta.Earthing detection unit includes ground fault indicator light, malfunction indicator lamp and programmable logic
Device connection.
Earthing detection unit uses double pincers method measurement of Grounding Resistance values, easy to operate, can be in continuous switch power supply, normal
Tested when work, it is not necessary to be inserted into measuring probe, tested electrode need not also be separated, it is only necessary to double clamps earth conductor just
Ground resistance can be measured: precision is high, and precision can achieve 0.01 Ω；Strong antijamming capability can filter out various power frequencies
Harmonic wave.
Earthing detection unit is furnished with auto-transformer T1 (voltage clamp) and current transformer Ta (current clamp), auto-transformer
T1 provides a potential E in the loop, and generates electric current I in tested circuit, by the measurement to E and I, by Ohm's law: R
=E/I can acquire the value of ground resistance；And the ground resistance standard value for being input to programmable logic device and setting is compared
Compared with judging whether to meet the requirements.If after being judged as failure, output control signal disconnects operation relay, ground fault indicator light
Alarm, to achieve the purpose that cut off main circuit, protection electrical equipment and life safety.
As shown in figure 3, detection of electrical leakage unit includes current transformer Tb, it is protected in the Three-phase five-wire of protector power supply
Phase line and zero curve pass through the annular core of current transformer Tb, and the zero curve of current transformer Tb and Three-phase five-wire is isolated with high resistant
Circuit connection.Concatenated test button SB and current-limiting resistance RL is connected between the zero curve and firewire of Three-phase five-wire.Detection of electrical leakage
Unit further includes PE line, and the both ends of PE line are separately connected the zero curve of Three-phase five-wire, device housings and high resistant isolation circuit.It is programmable
LED display panel and parameter setting panel are also connected in logic device.
The PE line termination device shell of detection of electrical leakage unit, other end independent grounding or access zero curve；Work as equipment leakage,
When its shell voltage-to-ground reaches programmable logic device setting danger numerical value, operation relay is disconnected, is cut off the power.It is protected
Three-phase phase line and the neutral conductor pass through the ring-shaped core of current transformer Tb, constitute the primary coil of mutual inductor, are wrapped in annular
Winding on iron core constitutes the secondary coil of current transformer Tb, if not leaking electricity generation, at this moment flow through three-phase phase line and
The current vector of the neutral conductor and it is equal to zero, therefore corresponding induced electromotive force can not be generated on secondary coil.If it happens
Electric leakage, three-phase phase line, the neutral conductor current vector and be not equal to zero, just make to generate induced electromotive force on secondary coil, this
Signal will be sent in programmable logic device, disconnect operation relay.
Since detection of electrical leakage unit is a protective device, it is whether intact, reliable that it should be inspected periodically.Pass through test
Can the series connection of button SB and current-limiting resistance RL be simulated leakage path, be operating normally with check device.LED display panel is used for
The data information for showing detection, can set various standard values in programmable logic device by parameter setting panel.
Claims (8)
1. a kind of protector circuit protects detection system, which is characterized in that including programmable logic device, the programmable logic device
It is connected with A/D sample circuit and operation relay, the A/D sample circuit is connected with high resistant isolation circuit, the high resistant isolation
Circuit is connected separately with three-phase electricity detection unit, earthing detection unit and detection of electrical leakage unit；The three-phase electricity detection unit connects
Ground detection unit connects to be electrically connected with the Three-phase five-wire of protector power supply with detection of electrical leakage unit.
2. protector circuit according to claim 1 protects detection system, which is characterized in that the three-phase electricity detection unit
Including over-voltage indicator light, under-voltage indicator light and phase shortage indicator light, the over-voltage indicator light, under-voltage indicator light and phase shortage indicator light are equal
It is connect with programmable logic device.
3. protector circuit according to claim 1 protects detection system, which is characterized in that the earthing detection unit packet
Auto-transformer T1 is included, the tap-changing windings one of the auto-transformer T1 terminate Three-phase five-wire firewire, another termination Three-phase five-wire
Zero curve and high resistant isolation circuit；The voltage adjusting end of the auto-transformer T1 connects ground terminal by conducting wire and electricity is isolated in high resistant
Road, is provided with current transformer Ta between the voltage adjusting end and ground terminal, the current transformer Ta and high resistant isolation circuit connect
It connects.
4. protector circuit according to claim 1 protects detection system, which is characterized in that the earthing detection unit packet
Ground fault indicator light is included, the malfunction indicator lamp is connect with programmable logic device.
5. protector circuit according to claim 1 protects detection system, which is characterized in that the detection of electrical leakage unit packet
Current transformer Tb is included, the phase line and zero curve in the Three-phase five-wire of the protector power supply pass through the annular iron of current transformer Tb
Circuit connection is isolated with high resistant in the output lead of core, the current transformer Tb.
6. protector circuit according to claim 5 protects detection system, which is characterized in that the zero curve of the Three-phase five-wire
Concatenated test button SB and current-limiting resistance RL is connected between firewire.
7. protector circuit according to claim 5 protects detection system, which is characterized in that the detection of electrical leakage unit is also
Including PE line, the both ends of the PE line are separately connected the zero curve of Three-phase five-wire, device housings and high resistant isolation circuit.
8. protector circuit according to claim 1 protects detection system, which is characterized in that on the programmable logic device
It is also connected with LED display panel and parameter setting panel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910609622.7A CN110208594A (en) | 2019-07-08 | 2019-07-08 | A kind of protector circuit protection detection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910609622.7A CN110208594A (en) | 2019-07-08 | 2019-07-08 | A kind of protector circuit protection detection system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110208594A true CN110208594A (en) | 2019-09-06 |
Family
ID=67796615
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910609622.7A Pending CN110208594A (en) | 2019-07-08 | 2019-07-08 | A kind of protector circuit protection detection system |
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| Country | Link |
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| CN (1) | CN110208594A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202940563U (en) * | 2012-09-04 | 2013-05-15 | 南京德和电气有限公司 | Intelligent leakage detection grounding resistor protection device |
| CN103532087A (en) * | 2013-10-14 | 2014-01-22 | 北京航天发射技术研究所 | Intelligent monitoring unit for vehicle-mounted single-phase alternating-current power supply |
| CN205724867U (en) * | 2016-06-24 | 2016-11-23 | 西安科技大学 | A kind of small current grounding system single-phase grounding selecting protection device |
| CN206991071U (en) * | 2017-06-20 | 2018-02-09 | 深圳市康元电气技术有限公司 | The long-distance monitorng device of oil production equipment |
| CN208172103U (en) * | 2018-05-28 | 2018-11-30 | 西安朗信电子技术有限公司 | A kind of ground resistance measuring instrument |
| CN210222113U (en) * | 2019-07-08 | 2020-03-31 | 成都通用整流电器研究所 | Circuit protection detection system of protector |
-
2019
- 2019-07-08 CN CN201910609622.7A patent/CN110208594A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202940563U (en) * | 2012-09-04 | 2013-05-15 | 南京德和电气有限公司 | Intelligent leakage detection grounding resistor protection device |
| CN103532087A (en) * | 2013-10-14 | 2014-01-22 | 北京航天发射技术研究所 | Intelligent monitoring unit for vehicle-mounted single-phase alternating-current power supply |
| CN205724867U (en) * | 2016-06-24 | 2016-11-23 | 西安科技大学 | A kind of small current grounding system single-phase grounding selecting protection device |
| CN206991071U (en) * | 2017-06-20 | 2018-02-09 | 深圳市康元电气技术有限公司 | The long-distance monitorng device of oil production equipment |
| CN208172103U (en) * | 2018-05-28 | 2018-11-30 | 西安朗信电子技术有限公司 | A kind of ground resistance measuring instrument |
| CN210222113U (en) * | 2019-07-08 | 2020-03-31 | 成都通用整流电器研究所 | Circuit protection detection system of protector |
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